by Alan Gomez, USA TODAY

by Alan Gomez, USA TODAY

The Social Security Administration estimated Wednesday that a Senate bill to overhaul immigration laws and legalize 11 million unauthorized immigrants would boost the retirement program's trust fund and help the economy.

In a letter to Sen. Marco Rubio, R-Fla., one of the members of the Senate "Gang of Eight" that is pushing for the overhaul, Social Security Chief Actuary Stephen Goss estimated the bill would add 3.2 million jobs, increase the country's gross domestic product (GDP) by 1.63% and bolster the Social Security trust fund over the next 10 years.

Goss stated that many are working in an "underground economy" and don't pay taxes, so adding them to the tax rolls will bolster the nation's coffers. And if the security provisions of the bill reduce illegal immigration in the future by half a million people per year, Goss predicted a net positive for the country's retirement program.

"We estimate a significant increase in both the population and the number of workers paying taxes in the United States as as result of these changes in legal immigration limits," Goss wrote. "Overall, we anticipate that the net effect of this bill on the long-range (Social Security trust fund) actuarial balance will be positive."

However, those who oppose legalization of unauthorized immigrants, such as the Heritage Foundation, say allowing 11 million people who are largely low-skilled to access U.S. taxpayer-funded social benefits will cost more than it generates. A recent Heritage study predicted the bill would cost the country $6.3 trillion over the next 50 years.

The proposal from the Gang of Eight expands immigrant visa programs to attract more highly-skilled foreigners trained in science, technology, engineering and mathematics but also creates a new class of visas for lower-skilled immigrants to work in retail, hospitality, janitorial and construction work.